This invention relates to a connection for an assembly of elements for installation on the wearable part of a structure engageable with abrasive material and, more particularly, to a connection featuring a bi-stress lock.
This invention in one embodiment is an improvement on co-owned U.S. Pat. No. 4,716,666. In that patent, a pair of spaced apart dovetails were employed to provide a readily replaceable wear element assembly--as for the underside of an excavating bucket. The assembly of the base element and wearable element was intended to be maintained in assembled relation by angling the dovetails so that the force of the normal material flow would drive the mating dovetails in tighter seating (or mating) engagement. To maintain the assembly against a force in the opposite direction--as in bucket "backslap", the ends of adjacent assemblies were butted together and held in series by a stop welded in front of the forward-most assembly.
According to the instant invention, we can provide extended portions on each of the male and female dovetail elements so as to develop opposed and confronting faces. These are adapted to receive locking members which can avoid the need for the onerous securement of the aforementioned stop. The invention has application not only to the wearable element assembly of the '666 patent but can be employed for other connections where at least one of the elements is subject to abrasive wear. Illustrative of other applications are those involving excavators where the inventive connection can be employed to releasably secure a shroud or series of shrouds to a bucket lip or to releasably secure a tooth adapter to a bucket lip.
The invention can be characterized generally in providing a bi-stress lock type connection for first and second relatively elongated mated elements where at least the second element has a surface subject to abrasive wear, the elements being movable into mating relation by movement of one relative to the other along a path parallel to the longitudinal center line of the elements. The elements, when mated, have adjacent spaced apart, generally planar surfaces at corresponding ends thereof and extend at an angle to the longitudinal centerlines. The planar surface in one of the elements is provided by a generally rectangular cavity therein and a generally rectangular block is mounted in the cavity engaging the spaced apart planar. surfaces. By this, the component of a force parallel to the longitudinal centerlines tending to unmate the elements imposes a compression and shear stress on the block so as to lock the elements in mated condition. Further, at least one of the elements has a wall portion substantially covering the block.